The Primer's core mechanism is not that it contains all knowledge—it's that it teaches by withholding.

The device shows each child exactly what they're cognitively ready for in that precise moment, no more, no less, which means this is the opposite of democratization and is instead individualized rationing dressed as liberation.

When Nell uses the Primer, she doesn't become equal to privileged children through access. She becomes unequal in a different way: she can follow a learning curve her own neurology permits.

The Phyla storyline proves the inversion—Phyla has every educational advantage like tutors, environments, and cultural capital, yet the Primer still treats her the same way it treats Nell as a cognitive system with actual limits. The technology doesn't erase those limits, but it maps them with surgical precision. Stephenson embeds this most clearly in how the Primer responds to failure: when a child can't grasp something, the device doesn't simplify universally but instead pivots for that specific brain.

The teaching method becomes a measure and the measurement becomes destiny—two children using identical technology emerge from it stratified not by resources but by what their minds could process in real time. Technology doesn't eliminate class; it makes class invisible by making it neurological, so the Rithmatist caste emerges not from conspiracy but from measurable differences in pattern recognition and abstract reasoning that even the most equitable technology on earth can't erase, only document and exploit.